Mittwoch, 2. Juli 2014

How to SEO pdf files

If your task is to optimize a pdf file for search engines, you must ensure, that your pdf file will be text sourced and not image-sourced. To do so, create your pdf file with a text editor like Libre Office / Open Office or the like, and never with an image editor like Photoshop.

The SEO for pdf procedure isn't tricky, but the optimization quality depends vitally from your general HTML and SEO knowledge:

NOTE!A pdf-file might contain following formats of meta descriptions:

schema name and description

namespace URI

preferred namespace prefix

Adobe PDF schema

"http://ns.adobe.com/pdf/1.3/"

pdf

Dublin Core schema

"http://purl.org/dc/elements/1.1/"

dc

EXIF schema for EXIF-specific properties

"http://ns.adobe.com/exif/1.0/"

exif

EXIF schema for TIFF properties

"http://ns.adobe.com/tiff/1.0/"

tiff

Photoshop schema

"http://ns.adobe.com/photoshop/1.0/"

photoshop

XMP Basic Job Ticket schema

"http://ns.adobe.com/xap/1.0/bj"

xmpBJ

XMP Basic schema

"http://ns.adobe.com/xap/1.0/"

xmp

XMP Media Management schema

"http://ns.adobe.com/xap/1.0/mm/"

xmpMM

XMP Paged-Text schema

"http://ns.adobe.com/xap/1.0/t/pg/"

xmpTPg

XMP Rights Management schema

"http://ns.adobe.com/xap/1.0/rights/"

xmpRights

The only usable imho is the Dublin Core Metadata Element Set, Version 1.1, the shorter
version of both versions, with 15 properties. They are however, fully enough to describe any pdf file to make it indexable for search engines. You can easy embed this type of
metadata using the namespace (XMLNS) declaration and HEAD definitions. How to use Dublin Core more detailedly read please this article about using of Header data for SEO purposes.

Like you probably already suspect, i recommend to begin the search engine optimization of any pdf file with creating a HTML file with the content, from which you later generate a pdf.

Create in a HTML editor of your choice a HTML file with the content you want finally present as pdf file. While creating use all OnPage SEO techniques you know. Especially make use of H1-h6, keyword dropping, internal linking with correct chosen anchors and semantic microdata markup. I recommend to add the header meta-data while you edit your HTML version of the document, even though this possibility exists in the text editor. Cause while editing of HTML file with a text editor, your document gets from text editor its own unnecessary HTML/CSS formats. Beside of this, text editors have just limited possibilities to add meta-tags. If you want, that your header meta-data will be visible in Acrobat Reader, after you generate the pdf file, write your meta-data in uppercase, like

<META NAME="" CONTENT=""/>

It isn't important which case you take for meta-data values, only meta-data in them own must be in uppercase. Like i mentioned before don't use any metadata beside of Dublin Core: only metadata types listed above will be wrapped into the pdf file container! The most descriptiv metadata type from the listed is Dublin Core.

After your content is ready as HTML file, open this file in text editor like Libre Office.

If you added meta-data to your document as you edited it as HTML, go directly to the article 6. If your HTML file misses the header meta-data, add some meta-data to your document in the "Properties" dialog of Libre Office. This dialog has limited functionality and allows only adding of meta-data in the form

<META NAME="" CONTENT=""/>

NOTE! Text editor doesn't allow adding of

<link rel="" href=""/>

It is better, as i mentioned, to add all your meta-data while editing your file as HTML.

In the "Properties" you get a tabbed window, the second tab of it contains default fields to fill:

title (adds meta title)

subject (adds meta classification - never heard about such meta tag)

keywords (adds meta keywords)

description (adds meta description)

In the third tab are located the user-defined description fields, which values will be added to the HTML header like meta-data. Possible values are:

text

datetime

date

duration

time

yes/no

After saving the document properties, select from menu file->export as PDF. You get a prompted dialog window with 5 tabs, where you have to check some options, before you save your fully SEO-ed pdf file: